In a medium bowl, whisk together eggs, vanilla, and milk. Add the flour and salt mixture and whisk until the batter is somewhat thick–about the texture of heavy cream or pancake batter. Cover and refrigerate for 2 hours. The resting and cooling process helps the rosettes be more crispy, but it isn’t necessary.

When ready to make the rosettes, heat about 3-4 inches of oil in a heavy saucepan. Place a candy thermometer in the saucepan. Heat the oil until it is 350-365 degrees.

Screw the rosette iron you want to use onto the handle. When the oil has reached 350-365 degrees, remove the batter from the fridge and pour some into a flat bottomed container–use a glass, pottery, or metal container–don’t use plastic or anything that will melt from heat of the rosette iron as you dip it in. This will be your working batter. Return the remainder of your batter to the fridge to stay cool.

Carefully submerge the iron in the oil for about 10-20 seconds to heat it (20 seconds for the first few, then 10 after you’ve used the iron a few times). Lift it out of the oil and dip it into the working batter, being careful to cover the bottom and sides of the iron but not the top of the iron. Quickly lift the iron out of the batter and submerge the batter-covered iron into the hot oil, making sure it’s completely covered with oil but not touching the bottom. The oil will bubble and foam quite a bit at this point. Let the rosette fry for about 40 seconds or until it is a light brown. When it’s done, lift the iron with the rosette out of the oil. With a fork or butter knife, carefully remove the rosette to a paper-towel lined plate to drain. Every so often a rosette may come off of your iron while it’s in the oil. That’s OK. Just let it fry until it’s light brown and then remove it from the oil to drain.

Repeat the process. As you get low on working batter, add more of the batter from the fridge. You will notice that the working batter will become warm as you work with it and will stop attaching to the rosette iron. As this happens, replenish with new, cold batter.

Once the rosettes are drained and cooled, place on a new plate and sift powdered sugar over the top of each. Store in an airtight container.